Method of regulating electric circuits.



No. 684,|65. Patented Oct. 8, I90I. M. H. BAKER.

METHOD OF BEGULATING ELECTRIC CIRCUITS.

A umion filed Supt. a, 1899.)

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METHOD OF REGULATIIIG ELECTRIC CIRCUITS.

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No. 684,I65. Patented Oct. 8, I90l. M. H. BAKER.

IETHOD 0F REGULATING ELECTRIC CIRCUITS.

(Application fllnd Sept. 5, 1899.)

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UNITED STATES PATENT OFFICE.

MALCOLM H. BAKER, OF NEW YORK, N. Y., ASSIGNOR TO THE MANHATTAN GENERALCONSTRUCTION COMPANY, OF NEW YORK.

METHOD OF REGULATING ELECTRIC CIRCUITS.-

SPECIFIGATION forming part of Letters Patent No. 684,165, dated October8, 1901.

Application filed September 5,1899.

lating Electric Circuits, of which the following is a specification.

My invention relates to improvements in.

regulators for circuits containing alternatingcurrent arc-lamps arrangedin series. Heretofore the regulation of this class of devices has beenaccomplished through the medium of very complicated and expensiveapparatus.

By means of my present invention all complication is avoided and theregulation of the current in an alternating arc-lamp series circuit ismade certain and effective by the use of very simple mechanism havingfew parts and very little liable to get out of order.

My invention relates, broadly, to automatically varying the reactance ina circuit such as described to compensate for changes in the resistanceof the circuit due to the cutting in or out of lamps or to any othercause. Otherwise expressed, my invention relates to automaticallyvarying the value of a variable reactance in the circuit in accordancewith changes of resistance in the said circuit in such a manner as tomaintain the current practically constant.

In carrying out my invention I include in the circuit in series with thelamps a reactance device consisting of a coil of wire so placed as tohave a free relative movement with respect to a laminated core insidethe coil. It is well understood that the current passing through a coilhaving such a relation to a magnetic core is more or less choked orimpeded, according to the relative position which the coil and the coreoccupy, the choking or impeding effect increasing with the farther andfarther insertion of the core within the coil and decreasing with thegradual withdrawal of the core from the coil. The

relative movements of the coil and the core may be brought about byvariations of the magnetic pull due to variations of the -currentpassing through the coil. If now a force could be discovered which wouldautomatically vary the choking effect produced in the Serial No.729,437- (No specimens.)

coil in correspondence with variations in the resistance of the circuit,whichforce should oppose and vary with the magnetic pull of the saidcoil, the value of the current traversing the coil might be madepractically independent of the resistance of the circuit, so that aconstant current could be maintained irrespective of the number of lampsin operation in the circuit. I have discovered that such a force can besupplied mechanicallyiii several ways. In the present instance I makeuse of a com pensating-lever carrying a weight, and I attach to the endof the said lever remote from the weight either the laminated core orthe coil, as the case may be, of a reactance device, and I pivot thesaid lever at such a point as to form a critical angle between the outerpart of the lever and the inner part-that is to say, the two parts ofthe lever on opposite sides of the pivotit being presupposed that theinner part of the lever will be approximately horizontal when themagnetic pull of the coil is at its minimum, while the outer portion ofthe lever will be in a position of least effectiveness at the samemoment. A simple way of determining the critical angle for the le ver ofthe compensating device is to construct a coil having a sufficientnumber of turns to show the proper voltage and amperage under thecondition of no load and then to connect the moving part of theapparatus containing the coil with a straight lever pivoted at a pointbetween its ends and carrying at its outer end a sliding counterbalance.Then by cutting into the circuit successively one lamp after anotheruntil the maximum number of lamps is cut in and at each successive stepsliding the counterbalance into such a position that the readings of theammeter will always show the normal current on the line it will be foundthat between the extreme limits of its movement the slidingcounterbalance will have traveled through a curve which is approximatelythe arc of a circle. It is manifest that the center of the are thusdescribed lies outside the pivot of the straight lever. The objectsought by making the lever angular is to utilize this pivot as thecenter of motion, so that a weight at- 10:)

tached to the end of the lever by some permanent means of attachment,such as suspension, will during the movements of the movable part of thereactance device from one extreme of its motion to the other followsubstantially the same curve as that traversed by the slidingcounterbance already described. It will be understood that as lamps aresuccessively cut into the circuit in the process described above thesliding counterbalance has to be moved by hand nearer and nearer to thepivot in order to meet the conditions set forth above, and it will alsobe understood that the counterbalance moves at the same time through acurve in a downward direction, each successive change in the position ofthe counterbalance representing a single unit of movement correspondingto the switching in of a single lamp or other unitary translatingdevice. The same will be true respecting the action of a weight of equalamount permanently attached to the end of a bent lever, provided theangle given to the leveris selected according to the method abovedescribed. We may suppose, for example, that the circuit is to carry acurrent of two thousand volts and seven amperes. The first requirementis that a coil should be provided having a sufficient num ber ofWindings to meet the described conditionsand being provided with a coreof suffioient size to avoid undue heating. These conditions beingattained it is easy to determine the critical angle for the lever. In aworkingcircuitincluding a maximum of thirty-three lamps and designed tooperate at about seven amperes of current I have found it suitable touse a lever having approximately the proportions illustrated in Figures1 and 2 of the drawings of the present application, the length of theinner and outer arms being, respectively, about twelve and one-half andtwenty-two inches and the Weight being about fifty pounds. Theseproportions l have employed in connection with a coil of No. 12 doublecotton wire having about one thousand turns in combination with alaminated iron core having a cross-section of about six inches by fourand one-half inches and a height of about ten inches. The critical anglein this instance is about one hundred and fifty degrees.

I have illustrated my invention in the accompanying drawings, in whichFig. 1 shows my apparatus connected up in series with a single group oflamps, the position of the parts being that which they occupy when thecircuit is fully loaded. Fig. 2 is a similar view showing the positionof the reactance device at minimum load. Fig. 3 is a diagram of myapparatus connected up with two groups of lamps. Fig. 4 is a diagram ofmy apparatus connected up with three groups of lamps. Fig. 5 illustratesdiagrammatically my improved regulating-coil in connection with a singlearc-lamp. Figs. 6, 7, and 8 are diagrammatic views illustrating the modein which the proper angle for the compensating lever is determined.

In the drawings, 1 is a suitable source of alternating current, and 2and 3 are mains leading therefrom. The lamps are shown at 4 4., and theregulating or reactance coil appears at 5. Said coil is represented assurrounding one leg of a laminated-iron core of horseshoe shape, and itstop 6 is pivoted to the end of a lever 7, carrying on its remote arm 8 acounterweight 9. The said lever 7 S is pivoted to a suitable upright orstandard 10. The parts of my regulating apparatus described aresupported upon a suitable base 11, of insulating material. I may providea slot 12 in the lever 7 at its junction with the top of the coil topermit the free relative movement of the parts at that point.

It will be seen that the position of the coil v 5 at full load is one inwhich the magnetic pull with relation to the core is comparativelyslight. In this position the arm 7 is approximately horizontal, so as togive to the downward pull of the coil under magnetic influ ences itsgreatest possible effect. It will also be observed that the position ofthe weight 9 and the lever 8 is such that the effect of the said weightis at its minimum in this position of the parts. On the other hand, whenthe circuit has its minimum load, as illustrated in Fig. 2, themechanical pull of the weight is at its maximum, While the magnetic pullas between the core and the coil is also at its maximum. The weight ofthe counterbalance 9, having been properly selected, the adaptability ofthe described apparatus to the work of regulating the circuit dependsupon the critical angle between the parts 7 and 8 of the leverconnecting the weight and'the coil. When the proper angle is chosen, theincreased effectiveness of the weight as the coil travels downward inresponse to variations of the current caused by decreased resistance inthe circuit will bear a direct ratio to the increased choking effect inthe coil caused by the approach of the coil and the core relatively toeach other. In this way a practically constant current will bemaintained in the circuit at all times.

Figs. 3 and 4 show typical arrangements of the reactance or regulatingcoil for a plurality of circuits. The parts 13 are laminated-iron cores,one leg of which is surrounded by a coil included in a separate group.The operation is obvious.

It is immaterial whether the weight 9 or any other counterweight orforce is attached to the coil or to the core, the relative move- 'mentsof these two parts being the feature upon which the choking effectdepends. When the compensating-lever is attached to the core of thereactance device instead of to the coil, (it being assumed that the coilis arranged above the core,) the core itself forms part of themechanical force opposing the magnetic pull of the coil.

I may apply my regulating reactance-coil to a single-lamp structure aswell as to a circuit including a series of arc-lamps. In Fig.

5 I illustrate such an application. The regulating-coil is in thisinstance placed in series with the carbons-that is to say, it isconnected up in the main circuit of the lamp. Its action is preciselythe same as has already been described in connection with a series oflamps in circuit.

Figs. 6, 7, and S are diagrams intended to illustrate the mode ofdetermining the curve through which the counterbalance is to move, andthey accordingly constitute an illustration of the mode of determiningthe critical angle of the lever 7. In Fig. 6 a straight lever 15 isshown having one end attached to the coil 5 and having arranged near itsopposite end a sliding weight 14, acting as a counterbalance in themanner already described. The position of the weight 14 when there is noload on the circuit is represented in Fig. 6. As lamps are successivelyswitched into the circuit the coil 5 rises and the weight 14 descends,and in order to maintain a current of, say, seven amperes in the circuitat all times the weight has to be successively shifted toward the pivotof the lever 15. The three figures G, 7, and 8 illustrate, respectively,the position of the weight and the lever under conditions of no load,medium load, and full load, it being understood that the weight 14 hasbeen so shifted during the passage from one extreme condition of thecircuit to the other as to maintain the current on the line constant. Itis plain that the weight has during this process traveled through acurve the center of which is outside the pivot at the top of thestandard 10. The shifting of the weight in the process last described iscaused by hand, the weight being moved in every instance until thereadings of the am meter 16-show the normal amperage-say seven amperes.In order to make the described operation automatic, I permanently attachto the pivoted lever a weight, and I provide the lever with a criticalangle, such that the weight, while the circuit is passing through theconditions of no load, medium load, and full load, will occupy the samerelative position in a similar curve through the natural movements ofthe bent lever as the coil 5 is successively lifted. A standard orsupport of suitable height having first been selected, the bend in thelever can be so chosen as to utilize the selected standard by the meansindicated in dotted lines in Figs. 6, 7, and 8. The curve described bythe weight 14 is shown at 17, and the three successive positions alreadydescribed are indicated at 18, 10, and 20. The first step in determiningthe angle for the compensating lever is to drop perpendiculars from thepoints 18, 19, and 20, and then select a lever, as 8, of such lengththat the end to which the weight is to be permanently attached will outthese perpendiculars in a curve similar tothe curve 17. The anglebetween the dotted portion 8 and that part of the lever 15 appearing atthe right of the standard 10 is the critical angle for thecompensatinglever. In other words, the bent lever, made up of the arms 7and 8, is by virtue of the critical angle between the said arms able toaccomplish the same results as the straight lever 15 with the slidingweight 14 upon itthat is to say, the bent lever accomplishedautomatically what the straight lever can be made to accomplish by aproper shifting of the sliding weight. It has not been thought necessaryto show in Figs. 6, 7, and 8 the weight attached to the arm 8. It wouldbe similar, however, if shown to the weight 9 appearing in Figs. 1 and2.

More than one regulating reactance device may be employed in series withthe translating devices. Thus while a single twentyfive-lamp reactancedevice would be used on a twenty-five-lamp circuit, two such reactancedevices or a single fifty-lamp reactance could be employed on afifty-lamp circuit. In the former case each of the reactance deviceswould do a fractional part of the regulation so far as the lamps wereconcerned, although each would act, as described above, to compensatefor changes of resistance in the circuit as a whole.

I claim as my invention 1. The method of maintaining a constant currentin an alternating-current circuit including translating devices inseries and also including a reactance-coil in series with thetranslating devices, which consists in opposing to the magnetic pull ofthe coil a mechanical force, and so correlating the said mechanicalforce and the magnetic pull that the choking efiect of the coil willvary automatically to compensate for changes in the resistance of thecircuit.

2. The method of maintaining a constant current in analternating-current circuit including translating devices in series andalso including a reactance-coil in series with the translating devices,which consists in setting up an opposing action between the magneticpull of the coil and a mechanical force, and causing the said force tovary in such meas= nre that the operating parts of the reactance devicewill always assume relative positions adapted to compensate for changesin the re sistance of the circuit.

3. The method of automatically causing the varying choking efiects of areactance device due to changes in the relative positions of itsoperating parts, to maintain a constant current in analternating-current circuit containing translating devices in serieswith each other and with the reactance device, which consists inopposing to the magnetic pull of the coil of the reactance device amechanical force, and so adjusting this force throughout its eifectiverange of operation that on a change of resistance in the circuit,

it shall bring the moving part of the react ance device to equilibriumat such a point as to produce the proper choking eitect formaintainingthe current constant.

4. The method of maintaining a constant current in analternating-current circuit ineluding translating devices in series andalso including a reactance-coil in series with the translating devices,which consists in opposing to varying magnetic pulls of the said coil 5caused by variations in the resistance of the circuit, the automaticcorresponding variations of a mechanical force, after having first socorrelated the magnetic pull, the mechanical force, and the chokingeffect of the 1b coil that equilibrium between the first two I isattained under conditions which produce the proper choking effect formaintaining the current constant.

Signed at New York, in the county of New York and State of New York,this 7th day of August, A. D. 1899.

MALCOLM H. BAKER.

Witnesses:

WM. H. OAPEL, G. H. STOOKBRIDGE.

DISCLAIMER.

684,165.-I1IC6ZCOZ77L II. Baker, New York, N. Y. IMPROVEMENT IN METHODOF REGU- LATING ELECTRIC CIRoUiTs. Patent dated October S, 1901.Disclaimer filed February 1 1902. by the assignee, the llfcmhattcmGeneral Construction Compmty, of New York, N. Y. Enters its disclaimerTo that part of the specification identified as follows, to Wit: To theconstruction illustrated in Figure 5 of the drawings and described inthe specification in the following Words:

Fig. 5 illustrates diagrammatically my improved regulating-coil inconnection With a single arc-lamp.

I may apply my-regulating reactance-coil to a single-lamp structure asWell as to a circuit including a series of arc-lamps. In Fig. 5 Iillustrate such an application.

The regulating-coil is in this instance placed in series with thecarbons-that is to say, it is connected up in the main circuit of thelamp. Its action is precisely the same as has already been described inconnection with a series of lamps in circuit.7" [Qfiic'ial Gazette,February 25, 1.902.]

Disclaimer in Letters Patent No. 684,165.

DISCLAIMER.

68 l,165.-llIaZc/ lm II. Baker, New York, N. Y. IMPROVEMENT IN METHOD OFREGU- LATING ELECTRIC OlRoUns. Patent dated October 8, 1901. Disclaimerfiled February 1%, 1902. by the assignee, the Manhattan GeneralConstruction Company, of New York, N. Y. Enters its disclaimer 7 To thatpart of the specification identified as follows, to Wit: To theconstruction illustrated in Figure 5 of the drawings and described inthe specification in the following Words:

5 illustrates diagrammatically my improved regulating-coil in connectionwith a single arc-lamp.

I may apply my-regulating reactance-coil to a single-lamp structure asWell as to a circuit including a series of arc-lamps. In Fig. 5 Iillustrate such an application. The regulating-coil is in this instanceplaced in series With the carbons-that is to say, it is connected up inthe main circuit of the lamp. Its action is precisely the same as hasalready been described in connection with a series of lamps in circuit.[Official Gazette, February 25, 1.902.]

